The survival estimates are determined from the analysis of the data collected through the Product Surveillance Registry (PSR), a prospective, non-randomized multicenter, global study designed to monitor the performance of market-released cardiac therapy products.

A lead-related complication is considered to have occurred if, 30 days or more after the implant, a clinical observation is reported and a clinical action is taken. The lead need not be returned to Medtronic.

Click on Method for Estimating for further information.